Cognitive Assessment in Grappling Athletes Following Choke versus Nonchoke Submissions.

PURPOSE: Participation in Brazilian jiu-jitsu and mixed martial arts has increased over the last three decades. These sports feature submission attacks, including strangles. These strangles, termed "chokes" in this context, primarily limit blood flow to the brain via compression of neck vasculature. There has been discussion in literature of the possibility of measurable cognitive effects following transient choking episodes. The present study used the King-Devick test (KDT) platform, a tablet-based reaction time and accuracy task designed to measure participants' number recognition, cognition, and verbal expression. This task requires functional vision, saccadic eye movements, comprehension, and expression. METHODS: Volunteer participants were screened for exclusion (prior brain injury) criteria and survey information before testing. Athletes were tested with the KDT immediately before a Brazilian jiu-jitsu training session, again immediately after succumbing to either a choke ("Choke" arm) or nonchoke ("Non-Choke" arm) submission while sparring, and again after a 10-min rest period following the postsubmission test. Analysis was done on test failures, total test times, and individual difference scores between baseline and subsequent testing. RESULTS: Sixty-two (32 Choke, 30 Non-Choke) participants were analyzed. There was no significant difference between Choke and Non-Choke in test failures ( χ2 (1,62) = 1.25, P = 0.263), total times ( t (60) = 0.62, P = 0.540; 95% CI, -3.44 to 6.51), and individual difference scores ( t (60) = 0.29, P = 0.776; 95% CI, -2.41 to 3.21). CONCLUSIONS: There were no significant differences between study arms in any of the three analyzed measures. This suggests that cognitive functioning, as measured by the KDT, is not affected by transient choking episodes.

The safety of sportive chokes: a cross-sectional survey-based study.

Objectives: Sportive choking or strangling, known as a 'choke' in the combat sports community, is the practice of compressing the jugular veins and carotid arteries to threaten unconsciousness by lowering cerebral perfusion pressure. This is commonly practiced within combat sports and police/military combatives. The safety profile of sportive choking is underrepresented in the literature. The authors sought to explore the safety of sportive chokes. Methods: A convenience sample of visitors to two combat sports internet forums completed an anonymous web-based survey on choking experience and related symptoms. Descriptive statistics were used to describe the obtained data. Bivariate analysis was performed to elaborate on relationships between grappling experience and the number of times choked, between the number of times choked with pre-syncope/syncope, and between the duration of symptoms and the number of times choked with pre-syncope/syncope. Results: Overall, 4421 individuals completed the survey. One hundred and fourteen were excluded, leaving 4307 analyzed respondents. Ninety-four percent were male, 89.2% were ages 18-44 years. Seventy-nine percent had >1 year of grappling experience and 30% had >5 years. Of the 4307, 1443 (33.5%) reported being choked >500 times, 3257 (75.7%) have been choked to near-syncope, and 1198 (27.8%) have been choked unconscious. Two of the 4307 (0.05%) reported ongoing symptoms from chokes. Of the respondents, 94.3% felt applying a choke would be a safe and effective way to control a street fight; 83.6% felt that vascular neck restraint, the police combative equivalent of sportive choking, would be appropriate as an alternative escalation of force option. Conclusion: Based on a convenience sample of 4307 respondents' self-reported data, sportive choking appears to be safe. Only 0.05% experienced ongoing symptoms, which were likely not related to brain ischemia.

Comparison of Radiographs and Computed Tomography for the Screening of Anterior Inferior Iliac Spine Impingement.

PURPOSE: To compare radiographic and 3-dimensional (3D) computed tomography (CT) imaging modalities for the screening of anterior inferior iliac spine (AIIS) impingement by establishing imaging measurement related to the AIIS. METHODS: Anteroposterior and false-profile radiographs and 3D CT scans were obtained on 10 human cadaveric pelvises. On the anteroposterior view for each methodology, 2 measurements were calculated: distance to the most lateral AIIS from the 12 o'clock position on the acetabular rim, and the angle between the lateral AIIS and the sagittal plane. On the false-profile view for each methodology, 2 measurements were calculated: distance to the anterior AIIS from the 12 o'clock position on the acetabular rim, and the angle between the anterior AIIS and the sagittal plane. Inter-rater and intrarater reliability analyses were performed for both methods in addition to an intermethod analysis. RESULTS: The radiographic false-profile view was the most repeatable orientation, with intraclass correlation coefficients showing excellent reproducibility in both inter-rater (angle: 0.980, distance: 0.883) and intrarater (angle: 0.995, distance: 0.995) analyses. The mean distance from the 12 o'clock position of the acetabular rim to the most anterior/lateral aspect of the AIIS was 41.4 mm and 16.0 mm on the radiographic false-profile and anteroposterior views, respectively. Intermethod analysis showed a systematic, quantitative bias between modalities (anteroposterior view: -4.1 mm, 6.7°; false-profile view: -0.1 mm, 8.3°), which will remain relatively consistent as evidenced by the strong individual reproducibility of each measurement. CONCLUSIONS: AIIS morphology in relation to the acetabular rim 12 o'clock position and its angle relative to the sagittal plane can be quantitatively determined using either radiographic or 3D CT imaging modalities. CLINICAL RELEVANCE: Radiographic evaluation may be a valuable tool in the screening of AIIS impingement.

Radiographic Identification of Arthroscopically Relevant Acetabular Structures.

BACKGROUND: The anatomy of the acetabulum has been described extensively in the literature, but radiographic acetabular guidelines have not been well established. This study provides a radiographic map of acetabular landmarks in the hip. PURPOSE/HYPOTHESIS: The purpose of this study was to quantify the precise radiographic location of arthroscopic landmarks around the acetabulum. The hypothesis was that their locations were reproducible despite variability in the anatomy and positioning of pelvic specimens. STUDY DESIGN: Descriptive laboratory study. METHODS: Ten fresh-frozen cadaveric specimens were dissected, and radio-opaque hardware was placed for each landmark of interest. Anteroposterior (AP) and false-profile radiographs were obtained, and measurements were taken using a digital picture archiving and communication system. RESULTS: On AP radiographs, the direct and indirect heads of the rectus femoris were a mean 48.2 ± 4.6 mm and 44.7 ± 4.3 mm proximal to the teardrop line, respectively. The mean radiographic distance between their insertions was 5.0 ± 3.4 mm. Moreover, the anterior inferior iliac spine was a mean 11.5 ± 3.8 mm from the acetabular rim. On false-profile radiographs, the mean distance between the direct and indirect heads of the rectus femoris was 31.4 ± 6.2 mm. The mean distance between the superior margin of the anterior labral sulcus (the psoas-u) and the midpoint of the transverse acetabular ligament was 41.0 ± 5.7 mm. Additionally, the direct and indirect heads of the rectus femoris corresponded to the 2:30 and 1:30 locations on the acetabular clockface, respectively. The midpoint of the transverse acetabular ligament was located at 7 o'clock on the clockface. CONCLUSION: The most important finding of this study, determined by quantitative measurements, was that the described surgical landmarks had reliable locations on radiographs. Distances between landmarks as well as distances between landmarks and reference lines were reproducible in both AP and false-profile views. CLINICAL RELEVANCE: An understanding of how acetabular structures present on radiographs could lead to more accurate portal and hardware placement intraoperatively during arthroscopic surgery as well as better preoperative and postoperative assessments.

Exposure to DDT metabolite p,p'-DDE increases autoimmune type 1 diabetes incidence in NOD mouse model.

The incidence of autoimmune Type 1 diabetes (T1D) has been steadily rising in developed countries. Although the exact cause of T1D remains elusive, it is known that both genetics and environmental factors play a role in its immunopathogenesis. Whereas a positive association between p,p'-DDE, a DDT metabolite, and Type 2 diabetes (T2D) has been well established, its role in T1D development in an experimental animal model has never been elucidated. This study seeks to investigate the effects of DDE exposure on the development of T1D in a NOD mouse model. As T1D is a T-cell-mediated disease, the underlying mechanism of DDE action on T-cells was studied in vitro and, in the context of acute and chronic DDE exposure, in vivo by investigating lymphocytes' viability, proliferation, their subsets and cytokine profiles. Chronic high-dose DDE treatment, initiated in pre-diabetic 8-week-old NOD females administered twice weekly intraperitoneally with 50 mg/kg DDE, significantly increased diabetes incidence and augmented disease severity in treated animals. Whereas T-cell proliferation and cell viability in the spleens of treated mice were not affected, diabetogenic action of chronic DDE exposure was associated with a decrease in regulatory T-cells and a suppression of secretion of protective cytokines, such as IL-4 and IL-10. Interestingly, an acute high-dose in vivo treatment of 8-week-old NOD males with 100 mg DDE/kg, administered intraperitoneally every other day over a period of 10 days, increased T-cell proliferation and potentiated pro-inflammatory and TH1-type cytokine secretion, without affecting the splenocytes viability and the T-cell sub-populations. These results confirm that high-dose DDE treatments affect the immune system, in particularly T-cell function. In conclusion, this study shows for the first time that high-dose chronic DDE exposure exhibits a diabetogenic potential, with an underlying immunomodulatory mechanism of action, in the development of T1D in an experimental mouse NOD model.

Radiographic Identification of Arthroscopically Relevant Proximal Femoral Structures.

BACKGROUND: Anatomic landmarks located on the proximal femur have only recently been defined, and there is a lack of radiographic guidelines for their locations presented in the literature. With the confident identification of these landmarks, radiographs could provide more assistance in preoperative evaluations, intraoperative guidance, and postoperative assessments. PURPOSE: To quantify the radiographic locations of endoscopic landmarks of the proximal femur. STUDY DESIGN: Descriptive laboratory study. METHODS: Ten cadaveric specimens were dissected, and radio-opaque hardware was placed for each landmark of interest. Radiographs were obtained and measurements recorded in anteroposterior (AP) and Dunn 45° views. RESULTS: In the AP view, the gluteus medius insertion was located a mean 12.9 ± 2.4 mm and 34.7 ± 5.1 mm from the piriformis fossa and vastus tubercle, respectively. The piriformis fossa was a mean 14.8 ± 5.9 mm and 4.9 ± 1.9 mm from the anterior and posterior tips of the greater trochanter, respectively. The anterior and posterior tips of the greater trochanter were a mean 14.8 ± 5.1 mm from each other. In the Dunn 45° view, the piriformis fossa was a mean 13.3 ± 2.0 mm, and the vastus tubercle was a mean 21.5 ± 6.0 mm, from the gluteus medius insertion. Moreover, the vastus tubercle was a mean 33.5 ± 6.4 mm from the anterior tip of the greater trochanter and 31.6 ± 8.5 mm from the posterior tip of the greater trochanter. CONCLUSION: In spite of the variation in cadaveric sizes, quantitative descriptions of endoscopic landmarks were reproducible in clinical views. CLINICAL RELEVANCE: A detailed understanding of how the described landmarks present radiographically is relevant to preoperative planning, intraoperative evaluations, and postoperative assessments.